Myra Plekam moved her hand up and moved her body, a WPVI reporter on the scene said, seeming himself amazed by the rescue.

An ambulance raced Plekam to the Hospital of the University of Pennsylvania, where she was in critical condition Thursday.

"It feels outstanding to be able to pull somebody (out) alive," said Michael Resnick, the city's public safety spokesman.

Thirteen people were injured.

Firefighters -- apparently moved by the tragedy -- placed flowers at the collapse site.

Legal proceedings begin

The first lawsuit following the collapse was filed Thursday by attorneys for a 54-year-old woman pulled from the rubble by a firefighter.

Robert J. Mongeluzzi, who represents Nadine White, asked for a jury trial in her personal injury case against the building owner and the demolition company. He filed a motion in state court asking that the defendants preserve all written records and other evidence related to the building.

"Mrs. White was trapped in a nightmare when the collapse occurred," he said through a written statement. "She mourns for those who died and has asked us to do everything we can to require these defendants to preserve critical evidence and to make certain those responsible are held accountable by a jury."

White was working at the Salvation Army store when the collapse occurred. In papers filed Thursday, her attorneys indicated they would seek at least $50,000 in damages.

Famed prosecutor tours site

STB Investments, the owner of the collapsed building, issued a short statement through an attorney Thursday.

"Our heartfelt thoughts and prayers go out to the people affected by this tragic event. Please know that we are committed to working with the City of Philadelphia and other authorities to determine what happened yesterday."

Philadelphia assistant district attorneys Jennifer Selber and Edward Cameron and district attorney spokeswoman Tasha Jamerson toured the site Thursday.

Cameron specializes in prosecuting people accused of homicides for the city and is well-known nationally for prosecuting abortion doctor Kermit Gosnell.

CNN asked Jamerson why they were looking at the site.

"It's way too early to be discussing any aspects of the building collapse," she answered. "We took a tour of the scene just like the mayor's office took a tour and the police took a tour. Along with the rest of the city, the entire DA's office is thinking about and praying for the victims of yesterday's tragedy."

Crime scene units also toured the site.

Some saw it coming

People who work in the area had grown concerned in recent days about the demolition work.

"I knew that was going to collapse sometime soon, and it did today," roofer Patrick Glynn told CNN affiliate WPVI.

"For weeks, they've been standing on the edge, knocking bricks off, pieces off. You could just see it was ready to go at any time. I knew it was going to happen. I seen it. I said it 10 times. Ask these guys. Every day, I said, 'It's gonna collapse. It's gonna collapse.' "

Minerva Pinto works nearby. She and her co-workers thought the building looked precarious in the days before the collapse.

"We'd all seen in the past week that the building was really unstable because of the demolition," she told CNN's iReport.

But city officials said there were no known violations at the site.

"No violations, no complaints that we're aware of, and all permits were valid," Nutter said earlier.